Front-head construction for self-rotating hammer-drills.



' L. G. BAYLES. FRONT HEAD GONSTRUGTION FOR SELF ROTATING HAMMER DRILLS.

APPLICATION FILED JUNE 1, 1914.

1,126,942. Patented Feb. 2, 1915 WITNESSES: I INVENTOR ATTORNL';

Specification or" Blowers ia'conr.

lEELE-EZWEATZNG HIUJEEZETEK'ZBREELLKS.

a m em filed June 1, iifl-i Eerie! in). semen.

Z whom it ii/.(LZ/ concern.

linen n shat 1i, Tnwrs (1., BAYLES, a 1 has-ion, in the county or lcrthampton and State of Pennsylvania, have invented a certain new and useiullmprovement in Front-- Head Construction for Self-Emailing Hammer-Drills, or which the following is a specification.

This invention relates to self rotating hammer drills, and more particularly to a front head construction for drills of hills type for use in stoping or other drill ng where it is necessary to drill vertical holes in the roof of slope or enery."

The object oi this invention is 'co provide a front head construction for drills of this fiype which will prevent dust from the hole from penetraif into the moving e-arts of drill when ii; is used in veri'rical or nearly vertical drilling,

With this object in view a from head construction has been devised, a practical era hodiment oi which is represented in the accompanying drawing.

As shown the drill comprises a head block 1, to one side of which is secured an air feed 2 and to the other side of which is secured a drill cylinder 3 in which reciprocate-s a pision 2, izhe movement of which is governedhy desired form of valve mechanism, (not shown). I

piston given a step by step rotation by means of a fluted rifle bar 5 provided with-ordinary ratchet mechanism 6. This rifle bar 5 slides in a bore in the head or" the piston which core is provided with grooves which are engaged by flutes on the rifle bar 5.

0n the forward end of the piston is a hammer bar extension 8, which is provided with straight fiui/es 9. Fitting into the forward end of the cylinder 3 is a cylinder head 10. In the rearward portion of the cylinder head is a here 11 through which the hammer bar extension 8 projects. Forward of this is a larger bore 12. Forward of the cylinder head 10 is a front head 13 which is secured by bolts i l passing through lugs 15 to the cylinder 3 which is also provided with lugs 16 through which She bolts 1-; pass.

Roizaiahly mounted in she front head 13 is a sleeve 1' the rearward portion of a drill chuck l8.

lh' end oi. the from head 13 is provided a rear extension Zlflwhich also inpc the here 12, the rearward face 21 which the flange 19 "co prevent forwardino'rion of the sleeve 17. The sleeve 17 is bored to receive the hammer bar extension ofthe piston and is provided on its inner surface with grooves engaging the straight flutes 9.

Threaded to the sleeye 1? is a nose piece 22 of larger diameter than hhe sleeve, this nme piece forming the forward portion of the drill chuck 18. The thread is arranged in the same direction as the spiral flutes on the rifle bar 5 so that rotation the piston fiends totighten :Zhe forward poi-lion 22 lo rhe chuck. The rear face of this nose piece 92 overlaps the front end of the front head and prevents any dust falling on the from head of the drill from entering the drill cylinder at the joint between ighe'sc parts. The nose'piece 22 is bored out to receive the head 23 of theanril, block. the shank 25 of which projects through a; smaller bore into the interior of the shank portion 17 of the chuck so that it is struck by the hammer bar extension of the piston s. The threaded joint between the sleeve 17 and the nose iece 22 comes at such a point that the anvil block 2% can he removed. An angular longitudinal aperture 26 is nrovided. for the recepbion of the drill steel, (not shown), the rear end of which can then he struck by the anvil block 94. Rearwardly inclined passages 2'? are provided through the forward portion of the chuck from the anvil block bore so that any dust penetrating into the bore along the shank of the drill can easily escape and not work into the cylinder. Y

The operation of the device is as follows; The rotary movement of the piston caused by the fluted rifle bar 5 will be communicated to the drill chuck 18 by means of the straight flutes 9 er the hammer, bar extensionof the piston, causing relative rotation between the forward portion 22 and the front head 13. With drills of hrdinary con struction the dust falling from the hole works down into the moving parts of the drill, quickly resulting in destructive wear of the drill. in the presentforrn the joint between the chuck and front head is entirely covered by the overlapping rear end of the nose piece of the chuck. this means, and also by the rearwardly inclined passages I by the rotary from the anvil b 'o're,

affecting the moving parts. .1

While the chuck is here shown as rotated movement of the piston, communicated to'thc chuck by the fluted forward extension of the piston, it is obvious that other means may be employed without invention for directly or indirectly rotating the chuck and it is therefore to be understood that the present showing and description discloses only one s ecified modification of my invention, and otl ier forms and modifications are included in the spirit'and scope of the invention as expressed in the claims.

What I claim is 1. In a fluid operated percussive drill, a cylinder, a front head secured to said cylinder, a drill steel receiving chuck rotatably mounted in said front head, said chuck having a rearward portion provided with a flange engaging a rearward face of said;-

front head and a forward portion of larger diameteroverlapping the forward end of sa1d front head, means to secure said chuck port1ons together, said and means for rotating chuck.

2. In a fluid operated percussive drill, a cylinder, a front head secured to said cylinder, a drill bit chuck having a rearward portion rotatably mounted in said front 'dust 1s enti'rely prevented from entering the cylinder an head, and provided with "a'flange portion engaging a rearward face of said front head, and a forward portion of larger diameter overlapping the front end of said front head, and having a drill bit receiving bore, means for securing said chuck portions together, and means for rotating said chuck.

3. In a fluid operated percussive drill, a cylinder, a front head, a piston in said cylinder having a fluted hammer extension, a chuck sleeve rotatably mounted in said front head and having a flange engaging a rearward face of said front head, said sleeve having an internal bore provided with grooves engaged by the flutes of said ham mer extension, a nose piece overlapping'the forward end of the front head, said nose piece having a polygonal drill bit receiving bore, and a larger bore in the rearward por- 5 tion, an anvll bloqk in said larger bore hav-- ing a shank projecting into said chuck sleeve to receive the impact of said hammer extension, means to secure said chuck sleeve and said nose piece together and means for rotating said piston. I

In testimony whereof, I have hereunto set my hand.

Witnesses FRED. M. SLATEn, ARTHUR SMITH.

LEWIS c. BAYLus. 

